I. Technical Field
The present invention relates to a sealing element for use in a well and, more particularly, to a radially and axially expandable element having an especially large expansion rate in order to be able to be expanded radially against an inner wall of a pipeline.
The present invention is particularly, although not exclusively, suitable for use in oil and gas wells for providing a packer having a large expansion rate. In particular, the present invention allows for the provision of a metal-to-metal seal, but is also very well suited for providing an elastomer seal. Also, the present invention will be very well suited for use as an anchoring element against an inner wall of a pipe, such as in a pipeline, for example, and in that case advantageously in combination with the sealing element function.
II. Description of the Related Art
Frequently, it is desirable to be able to install a pressure tight plug or seal in an oil or gas well in order to isolate adjacent production zones from each other. In many cases, it will be necessary for such a plug or seal to have a relatively large rate of expansion, as the plug or seal is typically run through restrictions having a smaller diameter than the one within which the plug is to set before the plug or seal reaches the location at which it is to be set.
Currently, several alternative functional elastomer sealing elements providing a high expansion rate are available. In general, however, such alternatives have the disadvantage of having an insufficient pressure capacity, especially when the expansion rates are high. Additionally, such elastomer sealing elements are often difficult to release after use as the large expansion to which the elastomer sealing elements have been subject causes severe deformations of the elastomer material, which needs a long time to restore its original shape, i.e. retract.